1. Technical Field of the Invention
The present invention relates to channel and network communication systems and processes and, in particular, to a system and method for automatic dynamic loop address changing in a Fibre Channel environment.
2. Description of Related Art
There are two kinds of protocols for device communication: channels and networks. Channels, for example, between a master host computer and a slave peripheral device, transport a large amount of data at very high speeds over relatively small distances with little software overhead once data transmission commences. A channel provides a direct or switched point-to-point connection between a master and a slave that is hardware-intensive. Networks, on the other hand, usually interface many users and support many transactions, sharing a plurality of hosts and system resources, over medium to large distances. In network connections higher software overhead is generally acceptable as long as high connectivity is achieved.
The Fibre Channel Protocol ("FCP") is a new generation protocol that combines the best of these two disparate methods of communication in a single Open-Systems-Interface-like (OSI-like) stack architecture. Essentially, the Fibre Channel ("FC") is a multi-topology, multi-layer stack with lower-layer-protocols ("LLPs") for controlling the physical transport characteristics and upper-layer-protocols ("ULPs") for mapping LLP communication to and from higher-level software structures that are compatible with an Operating System. These ULPs include both channel and network protocols such as Intelligent Peripheral Interface ("IPI"), Small Computer System Interface ("SCSI"), and Internet Protocol ("IP"), among others.
One of the most desirable objectives in any multi-device communication system is the ability to "hot-plug," that is, the capability to delete, add, and/or substitute a device in a system without bringing the system down or incurring an inordinate amount of specialized software overhead. For example, in a master-slave channel communication system, it is extremely useful to be able to change the attached peripheral devices on the fly without having to re-boot the system or without erecting expensive software partitions between the Operating System and the protocol that is associated with the multi-device communication system.
Although the ULPs in the FCP stack offer the benefits of multi-protocol connectivity to both channel and network communication systems, they do not provide for the capability to dynamically alter the device configuration of the system without the aforementioned shortcomings. Moreover, many Operating Systems currently in use do not provide for structures that would facilitate dynamic reconfiguration of the devices disposed in an FC environment. Accordingly, it can be appreciated that because of the tremendous growth potential for FC-compatible computer systems, there is a manifest need for providing a cost-effective solution that ameliorates these and other drawbacks.